PLYMOUTH, Wash. (AP) — A Northwest Pipeline official says a pressure vessel rupture caused the March 31 natural gas explosion that injured five people and forced an evacuation at Plymouth in Eastern Washington.

Northwest Pipeline vice president Ed Brewer told a community meeting Tuesday night in Plymouth the company is still investigating what caused the rupture on the vessel that removes carbon dioxide from the gas before it's liquefied.

KEPR reports ( people at the meeting questioned the evacuation procedure and one man suggested installing a warning siren.

The explosion threw a piece of shrapnel that left a big gash in the side of a liquefied natural gas storage tank at the Williams Northwest Pipeline storage facility, which is across the Columbia River from Umatilla (yoo-muh-TIHL'-ah), Ore.

The facility supplies gas during times of high demand to customers in Washington and Oregon.


Information from: KEPR-TV,

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